Muffler and air cleaner



Aug. 23, 1932- H. e. KAMRATH 1,872,752

MUFFLER AND AIR CLEANER Filed Dec. 7, 1929 Qwmmtoz Patented Aug. 23, 1932 UNITED STATES PATENT OFFICE HERBERT G. KAMRATH, OF FLINT, MICHIGAN, ASSIGNOR TO A C SPARK PLUG COM- PANY, OF FLINT, MICHIGAN, A COMPANY OF MICHIGAN MUFFLER AND AIR CLEANER Application filed December 7, 1929. Serial No. 412,879.

One of the principal objects of this invention is to provide a simple, inexpensive and efficient device for muffling noises, which is particularly adapted for use on the air intake conduit of the carburetor of an internal combustion engine for mufliing the so-called intak noises.

Another object of the invention is to provide a device of the type described in the preceding paragraph, which is so constructed and arranged that there may be conveniently incorporated therein an air-cleaning element which will remove from the air passing through the device into the carburetor and engine cylinders the foreign matter carried thereby.

Still another object of the invention is to provide a combined muflling and air-cleaning device which is so constructed and arranged that it will have maximum efliciency both as a silencer and an air cleaner.

For a better understanding of the nature and objects of the present invention, reference is made to the following specification in which is described the preferred embodiment of my invention which is illustrated in the accompanying drawing.

In the accompanying drawing:

Figure 1 is a longitudinal section through a combined mufliing and air-cleaning device in which is embodied my invention.

Figure 2 is an intake end elevation, with parts broken away and in section. of the device illustrated in Figure 1.

In its preferred embodiment, as shown in the drawing, my muffling and air-cleaning device includes inner and outer, circumferentially spaced, substantially co-extensive cylindrical shells 10 and 11 which are closed at their opposite ends by heads 12 and 13. To maintain the shells 10 and 11 circumferentiall spaced and fixed with res ect to the hea s 12 and 13, there is preferabi provided in each of the heads, adjacent t e circumference thereof, a channel 14, into the recess between the inner walls of each of which one end of the inner shell 10 snugly fits; Each of the ends of the outer shell 11 fits snugly around the outer wall of one of the channels 14 which is crimped thereover, as indicated at 15, to secure the heads and shells in assembled relation.

In one side of the outer'shell 11 and substantially co-extensive in length therewith, there is provided an opening 16 through which communication between the atmosphere and the annular space 17 between the shells 10 and 11 is established. At a point diametrically opposite the opening 16, there is provided in the inner shell 10 an opening 18 which is substantially co-extens-ive in length therewith and through which communication between the annular space 17 between the shells 10 and 11 and the-space 19 within the inner shell 10 is established. In the head 13, there is provided an o ening 20 which is surrounded by an outward y extending neck 21 which is adapted to be assembled in telesco ic relation with the air intake conduit of tlie carburetor of an internal combustion engine and through which communication between the space 19 within the shell 10 and the air intake conduit of the carburetor is established. The opening 20 and the neck 21 may be coaxial with the shells 10 and 11 or, as shown inthe drawing, may be arranged with their axis eccentric to the axis of the shells 10 and 11, if this is desirable in order to facilitate installation of the device.

The device described above is adapted to be installed on an internal combustion engine with the neck 21 in telescopic relation with the air intake conduit of the carburetor thereof. When the device is so installed and the engine is runnin the air which is to be supplied to the car uretor will be drawn, through the opening 16, into the annular space 17 between the shells 10 and 11, through which it will fi'ow, part in a clockwise direction and part in a counter-clockwise direction, to the opening 18, as indicated by the arrows shown in Figure 2. The air will then be drawn, through the opening 18, into the space 19 within the shell 10, whence it will pass, through the opening 20 and the neck 21, into the carburetor and engine cylinders.

The sound waves generated in the induction system will travel through the induction system and be discharged therefrom, through the air intake conduit of the carburetor, into the interior of the shell 10. From the interior of the shell 10, there is but one path to the atmosphere and that is through the opening 18, the annular space 17 between the shells 10 and 11, and the opening 16. The repeated reflection, and consequent absorption and dis-- sipation of the sound waves, by the-walls of the device, as they follow this path to the atmosphere, results in almost total destruction of the audible sound waves before they reach the atmosphere and the device, therefore, functions very efiiciently as a muffler of the intake noises.

To remove foreign matter from the air passing through the device prior to its entry into the carburetor and engine cylinders, there is preferably provided in the space 17 between the inner and outer shells 10 and 11 a porous dust-collecting medium 22. This dust-collecting medium preferably consists of an oil-wetted fabric, such as that disclosed in my copending application S. N. 245,404, filed January 9, 1928, which has matured into Patent No. 1,829,401, dated October 27, 1931, woven or knitted from flat metallic ribbon, wound around the inner shell 10 a sufficient number of times to form a mass of the desired thickness.

When a dust-collecting medium is disposed in the space 17 between the inner and outer shells 10 and 11, the air which passes from the atmosphere into the carburetor'and engine cylinders necessarily passes therethrough. As the air passes through the dustcollecting medium, the foreign matter carried thereby is separated from the air and retained by the dust-collecting medium, with the result that the air which passes into the carburetor and engine cylinders is free from foreign matter. It is to be noted that, due to the locations of the openings 16 and 18 and the arrangement of the dust-collecting medium 22, the air passing through the space 17 and the dust-collecting medium 22, is caused to travel in a path parallel to the walls of the shells 10 and 11, and the Whole of the dust-collecting medium is most effectually utilized.

Although I have shown and described a preferred embodiment of my invention, it is to be understood that this has been done by way of example and not by way of limitation and that the scope of my invention is to be determined only by the appended claims.

I claim:

1. In a device of the class described, a shell which is substantially imperforate throughout its circumference except in a relatively narrow element substantially parallel to its axis, wherein there isprovided an opening, a shell which surrounds and is circumferen: tially spaced from the first mentioned shell and which is substantially imperforate throughout its circumference except in a relatively narrow element substantially parallel to its axis and substantially diametrically opposite the first mentioned element wherein there is provided an opening, closures for the annular space between the shells, and a dust collecting element filling the space be tween the shells.

2. In a device of the class described, a shell which is substantially imperforate throughout its circumference except in a relatively narrow element substantially parallel to its axis wherein there is provided an air discharge opening, a shell which surrounds and is circumferentially spaced from the first mentioned shell and which is substantially imperforate throughout its circumference except in-a relatively narrow element substantially parallel to its axis and substantially diametrically opposite the first mentioned element wherein there is provided an air intake opening, closures for the ends of the shells, an air discharge conduit associated with one of the closures and communicating with the space within the first mentioned shell, and a dust collecting element filling the space between the shells.

In testimony whereof I affix my signature.

HERBERT G. KAMRATH. 

